<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta content="text/html;charset=ISO-8859-1" http-equiv="Content-Type">
</head>
<body bgcolor="#ffffff" text="#000000">
Hi <br>
Dear all,<br>
Hope you will be fine and enjoying good health. <br>
I have very basic questions.<br>
1)i am trying to solve the jeans instability problem for spherical
geometryusing FLASH 2.5. when i run this problem for one dimensional
spherical geometry it gives the following error <br>
conditons for this problem are given below<br>
./setup testsph -1d -auto result success<br>
make result success<br>
cd object<br>
./flash2<br>
WARNING: desired timestep < dtmin, using dtmin<br>
24 1.4911E-01 1.0000E-08 | 0.000E+00<br>
<br>
abort_flash called. See log file for details.<br>
Calling MPI_Abort() for immediate shutdown!<br>
<br>
[0] MPI Abort by user Aborting program !<br>
[0] Aborting program!<br>
p0_18386: p4_error: : 1<br>
in log file there is following error <br>
abort_message: FATAL: find_center_of_mass: Mtot = 0<br>
can any body tell me why its is happening?<br>
2) My second question is when i run it for two dimensional spherical
goemetry. For this case when i choose r=1.5 cm there is more
density along the boundaries of circle (2-d spherical geometry. when i
choose r= 100 cm there is high density on centre in form of peak but
difference between maximum density and minimum density is small(like
max den=4.3*10^7 and min 9.9*10^6, while inital density is 1.5*10^7,
for cartesian coordinates max den=1.1*10^8, min 7.5*10^5, while inital
density is 1.5*10^7).<big></big> Intial conditions for problem are
given below.<br>
Can any one help me in this regard? I am not good user of FLASH,
trying to learn the FLASH. <br>
For two dimensional sperical geometry i am expcting centre collapse <br>
<br>
p0 = 1.5E0<br>
rho0 = 1.5E7<br>
lambdax = 5.0 kx=2pi/lambdax<br>
lambday = 1.E10 ky=2pi/lambday<br>
lambdaz = 1.E10 kz=2pi/lambdaz<br>
amplitude = 0.001<br>
Computational domain<br>
<br>
xmin = 0.0<br>
xmax = 1.0E2<br>
ymin =-1.0<br>
ymax = 1.0<br>
zmin = 0.<br>
zmax = 0.<br>
<br>
geometry = "spherical"<br>
<br>
xl_boundary_type = "reflect"<br>
xr_boundary_type = "periodic" <br>
yl_boundary_type = "periodic" <br>
yr_boundary_type = "periodic" <br>
zl_boundary_type = "periodic"<br>
zr_boundary_type = "periodic"<br>
nblockx = 2<br>
nblocky = 2<br>
dtini = 1.0E-5<br>
dtmin = 1.0E-8<br>
dtmax = 1.0E-2<br>
Gravity<br>
<br>
igrav = 1<br>
grav_boundary_type = "isolated"<br>
mpole_lmax = 0.0<br>
rho=rho0(1+amplitude(cos(krcos(theta)+krsin(theta)))<br>
p=p0(1+gamma*amplitude(cos(krcos(theta)+krsin(theta)))<br>
kj=sqrt(4*pi*G*rho0)/c0<br>
c0=sqrt(gamma*p0/rho0)<br>
<br>
I will be very thankful to you for ur kind help in this regard<br>
thanks in advance<br>
cheers<br>
M.A.Latife<br>
<br>
<br>
<br>
</body>
</html>